Arias has been converted from shortstop to the outfield for the Reds' Low-A affiliate in Dayton. He's hitting .270/.302/.436 with 33 stolen bases in 40 attempts.
That sort of stat line would be far more encouraging if Arias were still a shortstop. One other discounting factor is his horrific BB:K ratio of 8:59. Even with his speed, it'll be difficult for Arias to hit for average as he advances up the food chain.